Aldehydes are present in a wide range of substances, including body fluids (e.g. blood, urine, tears), breath, agricultural materials, meat, fish, poultry, and other commercial and natural goods. The production of aldehydes is a natural process in many materials that is related to various biologic, biochemical, and related conditions. The presence and/or concentration of an aldehyde in a material can therefore be useful to determine a biologic, biochemical, medical, or other status of the material (or material generating entity). As an example, the concentration of one or a group of these substances has a range of applications ranging from the assessment of oxidative stress in a living being to monitoring the relative freshness or potential adulteration of agricultural products (e.g., meat, fish, poultry, crops).
By way of a particular example application, oxidative stress (OS) is a term used to describe the level of damage in living organisms caused by reactive oxygen species at molecular and cellular levels. The level of OS can be determined by measuring certain biomarkers including, but not limited to, malondialdehyde (MDA) a dialdehyde with a three-carbon backbone. Oxidative stress biomarkers including MDA are present in many biological fluids, such as urine, blood, breath and tears.
While a variety of methods and apparatuses have been developed to determine the presence and/or concentration of aldehydes in these and similar applications, the known art suffers from various problems and undesirable characteristics. These include, but are not limited to one or more of: (a) lack of specificity, (b) the need for significantly elevated temperatures, (c) the use of strong acids, (d) complexity of testing/handling/storage requirements, (e) interference with the test results by unrelated compounds and background conditions, (f) unwanted (and sometimes interfering) byproduct(s) from test reagent(s), and (g) the time required for testing.